That's not your home Spock. Vulcan from your reality is fine. If you know more about what's going on than NuSpock, you should have come up with that conclusion rather than acting like this is the real deal. Not saying you shouldn't take the deaths of billions of Vulcans seriously, but for god's sake, quit calling it your home!
Which again, set's the precident of an altered timeline, not a parallel universe. Spock Prime knows that the life he lived, will not be the life that his younger self will now live. All events have been changed and he remembers what had been for him, since he was the 'center of the storm' so to speak. Now that it has, and Vulcan has been destroyed, it is still HIS Vulcan as this is still his reality (Just changed by Nero's time messing).
It would be the same as if he had lived his life, got sucked back in time 129 years by accident, without Nero messing with the events of time. He would still be there, the next 129 years would still happen, but nothing would have changed from his life's memories unless he directly interfered.
The fact that Nero came back and changed everything means that the timeline has now changed, so again, this is his Vulcan, so he would be effected by all the lives lost and the never-will-be's now. For all we know, Tuvok will not be born to serve on Voyager, will never go undercover with the Maquis, Voyager may never get sucked into the Delta Quadrant, which means they will never meet Seven of Nine. Janeway from 25 years into her future will never go back defeat the Borg Queen, ending the Borg race.
Even so, by the time this timeline cathces up, Voyager will be 3500 feet long and 136 decks....
Oh, never mind!